Tensile Deformation of a Nickel-base Alloy at Elevated Temperatures

Roy, Ajit K.; Venkatesh, Anand; Marthandam, Vikram; Ghosh, Arindam

doi:10.1007/s11665-007-9189-x

Cited by 37 publications

(9 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All the values have been normalized considering a reference value equal to maximum strength. Yielding stress and tensile strength of the base material are coherent with the data reported in literature for Waspaloy [10,18]. At temperature above 700°C, hardening disappeared justifying the decay of the tensile strength at high temperature.…”

Section: Static Testsupporting

confidence: 88%

“…A wide extension of the plastic zone is observed at temperature above 700°C (Fig. 2a), which is in contrast with the marked reduction observed in [10]. Assuming base material as a reference, the modification of the static behaviour induced by TIG is clearly highlighted.…”

Section: Static Testmentioning

confidence: 79%

“…Microstructure is characterized by a face centered cube matrix with dominant precipitates γ'. Ductility of Waspaloy has been studied in [10], showing a reduction starting from room temperature to about 300 °C, an irregular behaviour up to 600 °C and a quick reduction at higher temperature. Waspaloy can be welded using conventional or advanced welding techniques.…”

Section: Materials and Experimental Proceduresmentioning

confidence: 99%

See 2 more Smart Citations

Modification of creep and low cycle fatigue behaviour induced by welding

Carofalo¹,

Dattoma²,

Nobile³

et al. 2014

Frattura Ed Integrità Strutturale

View full text Add to dashboard Cite

ABSTRACT. In this work, the mechanical properties of Waspaloy superalloy have been evaluated in case of welded repaired material and compared to base material. Test program considered flat specimens on base and TIG welded material subjected to static, low-cycle fatigue and creep test at different temperatures. Results of uniaxial tensile tests showed that the presence of welded material in the gage length specimen does not have a relevant influence on yield strength and UTS. However, elongation at failure of TIG material was reduced with respect to the base material. Moreover, low-cycle fatigue properties have been determined carrying out tests at different temperature (room temperature RT and 538°C) in both base and TIG welded material. Welded material showed an increase of the data scatter and lower fatigue strength, which was anyway not excessive in comparison with base material. During test, all the hysteresis cycles were recorded in order to evaluate the trend of elastic modulus and hysteresis area against the number of cycles. A clear correlation between hysteresis and fatigue life was found. Finally, creep test carried out on a limited number of specimens allowed establishing some changes about the creep rate and time to failure of base and welded material. TIG welded specimen showed a lower time to reach a fixed strain or failure when a low stress level is applied. In all cases, creep behaviour of welded material is characterized by the absence of the tertiary creep.

show abstract

Section: Static Testsupporting

confidence: 88%

Section: Static Testmentioning

confidence: 79%

Section: Materials and Experimental Proceduresmentioning

confidence: 99%

See 1 more Smart Citation

Modification of creep and low cycle fatigue behaviour induced by welding

Carofalo¹,

Dattoma²,

Nobile³

et al. 2014

Frattura Ed Integrità Strutturale

View full text Add to dashboard Cite

show abstract

“…This could be attributed to the effect of dynamic strain aging, i.e., the interaction between dislocations and interstitial/substitutional atoms during plastic deformation at high temperatures. 19,20) The serrations were less obvious in the curves for the weld interface specimen than in the undiluted weld metal and transition zone specimens. The mechanism leading to the reduced amplitude of serrations of the weld interface specimen is not understood and requires further study.…”

Section: Microstructural and Compositional Analysismentioning

confidence: 95%

Microstructure and Stress Corrosion Cracking Behavior of the Weld Metal in Alloy 52-A508 Dissimilar Welds

et al. 2011

View full text Add to dashboard Cite

In the nuclear power industry, dissimilar metal welding is widely used for joining low alloy steel to austenite stainless steel components with nickel-base filler metals. In this study, attention was paid to the weld metal in multi-pass Alloy 52-A508 dissimilar welds. An approximately 2 mm wide transition zone was observed that consisted of a martensitic layer (10$20 um) along the weld interface and the austenite phase region with varying degrees of dilution. After post-weld heat treatment, the microstructures near the weld interface consisted of martensite, carbides and Type II boundaries. The presence of Type II boundaries significantly reduced the resistance to stress corrosion cracking (SCC) and formed intergranular cracking under simulated reactor coolant conditions. Constant extension rate tensile (CERT) tests were performed on the notched tensile specimens in 300 C water at two extension rates, 3 Â 10 À4 and 1 Â 10 À6 mm/s. A fast CERT test can be regarded to have no contribution of corrosion, and its results can be used as standards for comparison. In the slow CERT tests, the ductility losses of round-bar specimens with a circumferential notch at various regions in the weld metal were ranked accordingly. The relative susceptibility to SCC in terms of the ductility loss in increasing order of severity was as follows: the undiluted weld metal, the transition zone and the weld interface. SEM fractographic observations were consistent with the SCC results, i.e., an increased ductility loss or SCC susceptibility was associated with more brittle fractures.

show abstract

“…The microstructural analysis of precipitation-hardened Waspaloy showed the tendency of an initial unimodal γ′ precipitations size distribution to turn into a bimodal distribution as a result of continued aging [ 12 ]. Based on the results of tensile tests, Roy et al [ 13 ] indicated an absence of uniform strain of Waspaloy at the temperatures above 800 °C. The effect of the interrelationship between heat treatment and the forging of Waspaloy was investigated in the work presented by Donachie at al.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Hot Workability of Nickel-Based Superalloy Using Activation Energy Map and Processing Maps

et al. 2020

View full text Add to dashboard Cite

The stress-strain curves for nickel-based superalloy were obtained from isothermal hot compression tests at a wide range of deformation temperatures and strain rates. The material constants and deformation activation energy of the investigated superalloy were calculated. The accuracy of the constitutive equation describing the hot deformation behavior of this material was confirmed by the correlation coefficient for the linear regression. The distribution of deformation activation energy Q as a function of strain rate and temperature for nickel-based superalloy was presented. The processing maps were generated upon the basis of Prasad stability criterion for true strains ranging from 0.2 to 1 at the deformation temperatures range of 900–1150 °C, and strain rates range of 0.01–100 s−1. Based on the flow stress curves analysis, deformation activation energy map, and processing maps for different true strains, the undesirable and potentially favorable hot deformation parameters were determined. The microstructural observations confirmed the above optimization results for the hot workability of the investigated superalloy. Besides, the numerical simulation and industrial forging tests were performed in order to verify the obtained results.

show abstract

Tensile Deformation of a Nickel-base Alloy at Elevated Temperatures

Cited by 37 publications

References 12 publications

Modification of creep and low cycle fatigue behaviour induced by welding

Modification of creep and low cycle fatigue behaviour induced by welding

Microstructure and Stress Corrosion Cracking Behavior of the Weld Metal in Alloy 52-A508 Dissimilar Welds

Evaluation of Hot Workability of Nickel-Based Superalloy Using Activation Energy Map and Processing Maps

Contact Info

Product

Resources

About